• Radiation Oncology Journal
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• v.13 no.2
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• pp.113-120
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• 1995

Purpose : To investigate the effect of alkaloid fraction from Korean ginseng on radiation-induced DNA double strand breaks (dsb) formation and repair in murine lymphocytes Materials and Methods : We used the neutral filter elution technique to assay $^{60}Co\;{\gamma}$ ray-induced DNA double strand breaks formation and repair in C57BL/6 mouse spleen lymphocytes for evaluating the dose-response relationship in the presence of alkaloid fraction as a radioprotective agent. The lymphocytes were stimulated with Phytohemagglutinin (PHA, 2 u g/ml) to label $^3[H]-thymidine.$ Isotope-labelled lymphocytes in suspension were exposed to 100 Gy at $0^{\cdot}C$ in the alkaloid fraction-treated group and elution procedure was performed at PH 9.6. The extents of formation of radiation-induced DNA double strand breaks and repair were compared respectively via strand scission factor (SSF) and relative strand scission factor (RSSF). Results: Alkaloid fraction reduced the formation of double strand breaks with dose modification factor of 2 15, compared to control group Rejoining of DNA dsb appeared to take place via two components. The first fast component was completed within 20.4 minutes, but the second slow component was not completed until 220.2 minutes after irradiation. About $30\%$ of dsb formed by irradiation was ultimately unrejoined despite the administration of alkaloid fraction. The administration of alkaloid fraction had a great effect on the second slow component of repair; the half-time of fast component repair was not changed, but that of slow component was 621.8 minutes. Conclusion: Neutral filter elution assay Proved to be a very effective method to quantitate the extents of DNA dsb formation and its repair. By using this technique, we were able to evaluate the efficiency of alkaloid fraction from Korean ginseng as a valuable radioprotector. Alkaloid fraction can be used prophylactically to prevent or ameliorate the severe radiation damages in workers and neighbors around the atomic power plants. For more refined study, however, more advanced purification of alkaloid fraction wil be needed in the near future.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.305-312
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• 2019

The discovery of nitric oxide (NO) as a major signaling molecule in a number of pathophysiological processes - vasodilation, immune response, platelet aggregation, wound repair, and cancer biology - has led to the development of various exogeneous NO delivery systems. However, the development of ideal delivery system for human body application is still left as a challenge due to its high reactivity and short half-life in physiological condition. In this article, an overview of several nano-structures as potential NO delivery system will be presented, along with their recent research results and biomedical applications. Nano-size delivery system has immense advantages compared to others due to its high surface-to-volume ratio and capability for surface modification; thus, it has been proven to be effective in delivering nitric oxide with enhanced performance. Through this novel nano-structure delivery system, we are expecting to achieve sustained release of nitric oxide within adequate range of concentration, which ensures desired drug effects at the target site. Among different nano-structures, in particular, nanoparticle, microemulsion and nanofilm will be reviewed and compared to each other in respect of nitric oxide release profile. The proposed nano-structures for exogeneous NO delivery have a biological significance in that it can be further utilized in diverse biomedical fields as a highly promising therapeutic method.

• Clinical and Experimental Otorhinolaryngology
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• v.11 no.4
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• pp.275-280
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• 2018

Objectives. Middle vault deviation has a significant effect on the aesthetic and functional aspects of the nose, and its management continues to be a challenge. Spreader graft and its modification techniques have been focused, but there has been scarce consideration for removing surplus portion and balancing the upper lateral cartilage (ULC). This study aimed to report the newly invented triangular-shaped resection technique ("triangular resection") of the ULC and to evaluate its efficacy for correcting middle vault deviation. Methods. A retrospective study included 17 consecutive patients who presented with middle vault deviation and underwent septorhinoplasty by using triangular resection at a tertiary academic hospital from February 2014 and March 2016. Their outcomes were evaluated pre- and postoperatively including medical photographs, acoustic rhinometry and subjective nasal obstruction using a 7-point Likert scale. Results. The immediate outcomes were evaluated around 1 month after surgery, and long-term outcomes were available in 12 patients; the mean follow-up period was 9.1 months. Nasal tip deviation angle was reduced from $5.66^{\circ}$ to $2.37^{\circ}$ immediately (P<0.001). Middle vault deviation also improved from $169.50^{\circ}$ to $177.24^{\circ}$ (P<0.001). Long-term results were $2.49^{\circ}$ (P=0.015) for nasal tip deviation and $178.68^{\circ}$ (P=0.002) for middle vault deviation. The aesthetic outcome involved a complete correction in eight patients (47.1%), a minimally visible deviation in seven patients (41.2%) and a remaining residual deviation in two patients (11.8%). Pre- and postoperative minimal cross-sectional areas (summation of the right and left sides) were 0.86 and 1.07, respectively (P=0.021). Fifteen patients answered about their nasal obstruction symptoms and the median symptom score had alleviated from 6.0 to 3.0 (P=0.004). Conclusion. Triangular resection of the ULC is a simple and effective method for correcting middle vault deviation and balancing the ULCs without complications as internal nasal valve narrowing.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.351-363
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• 2007

Previously, we analyzed for nutrition knowledge and the use of nutrition knowledge in the everyday lives of students in order to develop nutrition education programs that focus on desirable behavior change. From this, we found that female students desired to participate in nutrition education more than male students, and regarding their concerns for nutrition education, 73.2% of the females and 50.0% of the males displayed interest in 'obesity and the regulation of body weight'. Therefore, this study showed female students give more attention to the obesity and the regulation of body weight than male students(p=.000<.001). In addition, female students had higher interests($8.63{\pm}1.67$) than male students ($7.45{\pm}2.03$) in nutrition knowledge(p=.000<.001). By investigating the use of nutrition knowledge in everyday life, our research indicated that the actual use of nutrition knowledge was less. To encourage students to persue dietary lives addressing the concerns confirmed above, the following needed to occur. 1) Provide them nutrition information for the main processed foodstuffs encountered when dining out(breads, cakes, cookies, and carbonated beverage). 2) Teach them to read food nutrition labels. 3) Help them find a lifestyle connection through lasting self-management methods and the generation of social support. Accordingly, this required developing effective and practical nutrition education programs that considered regional characteristics and gender differences. The most important factors considered during nutrition education program development were the need for motivation and ongoing education by stage of change, rather than temporal education through specific problem analysis, in order that those being educated may bring about a change of behavior by themselves. Therefore, from this study, we have suggested the use of multilateral operating strategies for successful nutrition education. In addition the phase model of behavior change should be applied. Our programs were aimed at self owned nutritional management so that students could master their own methods for acquiring skills and enjoying dietary life. The research may be summed up as follows. First, the purpose of education at the recognition stage of change was to attempt motivation for nutrition improvement, by analyzing the problems such as food buying habit and the main purchasing viewpoints when dining out. Second, the purpose of education at the action stage of change was to help students acquire of concrete methods for behavior modification by linking the program to their home as well as to teachers with various activities that suited the situation at school. This was done by analyzing the processes and decisions pertaining to dining out the main processed foodstuffs and principal components, etc. through data and experimental practice. Third, the purpose of education for changing of habits and values, or the maintenance stage, was to investigate the various reasons that undesirable behaviors were induced, and then determine a lasting self-management method as well as how to generate social support. If the nutrition education program developed in this study is utilized on site, someone in the primary role as the nutrition educator and trained specifically in nutrition, can help induce the health promotion in the community as well as lasting dietary management, by executing a link with families in parallel with educating teaching staff and students' parents. In addition, this program can playa role in the government policies related to the health promotion for our youth who are the foundation of our nation and who can enhance our national competitive power.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.5
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• pp.269-277
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• 2017

Recently, a submerged breakwater has been installing to prevent the erosion of shoreline everywhere. Artificially submerged breakwater is made to minimize the loss of nourishment sand beach erosion. For this reason, it has been indiscriminately constructed submerged breakwater that is planned in the country throughout. However, maintenance purposes to keep the shoreline of the beach is a method that is quite a few problems. There are also disadvantages such as expensive construction costs, ocean space utilization, water pollution and shoreline modification. In addition, person of utilizing the space of the ocean leisure does not like that because of the disconnection of ocean space. The beaches such as Gwanganri are artificially supplying nourishment sand to maintain the beach. The flexible construction method refers to a structure that is installed as a flexible material instead of submerged breakwater to prevent the loss of nourishment sand. In order to develop a new method to mitigate shoreline erosion, this study was carried out a hydraulic model experiment by installing a cell group as an example of the flexible method. Namely, in order to prevent the loss of nourishment sand, we decided to develop a new method that can mitigate the degree of beaches erosion by using cell group instead of submerged breakwater. In the two dimensional fixed hydraulic experiment, was carried out the effect reducing of wave height and the rate of low reflection due to the installation of the cell group. In movable bed experiment, the capture rate of the nourishment sand and the erosion prevention rate of the nourishment sand was performed for stability of shoreline. Therefore, according to the results of the hydraulic tests, it was possible to maintain the stable beaches due to installing the cell group on the erosion beaches, due to the effect of reducing wave height, the low reflection, the erosion prevention rate of nourishment sand, the high capture rate of nourishment sand.

• Korean Journal of Head & Neck Oncology
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• v.14 no.2
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• pp.156-163
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• 1998

Background & Objectives: Frameless fractionated stereotactic radiotherapy(FFSRT) is a modification of stereotactic radiosurgery(SRS) with radiobiologic advantage of fractionation without losing mechanical accuracy of SRS. Local recurrence of head and neck cancer at or near skull base benefit from reirradiation. Main barrier to successful palliation is dose limitation secondary to normal tissue tolerance. We try to evaluate the efficacy and safety of FFSRT as a new modality of reirradaton in these challenging patients. Materials & Methods: Seven patients with recurrent head & neck cancer involving at or near skull base received FFSRT from September 1995 to November 1997. Six patients with nasopharyngeal cancer had received induction chemotherapy and curative radiation therapy. One patient with maxillary sinus cancer had received total maxillectomy and postoperative radiation therapy as a initial treatment. Follow-up ranged from 11 to 32 months with median of 24 months. Three of 7 patients received hyperfractionated radiation therapy(1.1-1.2Gy/fraction, bid, total 19.8-24Gy) just before FFSRT. All patients received FFSRT(3-5Gy/fraction, total 15-30Gy/5-10fractions). Chemotherapy(cis-platin $100mg/m^2$) were given concurrently with FFSRT in four patients. Second course of FFSRT were given in 4 patients with progression or recurrence after initial FFSRT. Because IF(irregularity factor; ratio of surface area of target to the surface area of sphere with same volume as a target) is too big to use conventional stereotactic RT using multiple arc method for protection of radiation damage to critical normal tissue, all patients received FFSRT with conformal method using irregular static ports. Results: Five of 7 patients showed complete remission in follow-up CT &/or MRI. Three of these five patients who developed marginal, in-field, and out-field recurrences, respectively. Another one of complete responders has been dead of G-I bleeding without evidence of local recurrence. One partial responder who showed progressive disease 15 months after initial FFSRT has received additional FFSRT, and then he is well-being with symptomatic improvement. One minmal responder who showed progression of locoregional disease 9 months after $1^{st}$ FFSRT has received 2nd FFSRT, and then he is alive with stable disease. Five of 7 case had showed direct invasion to skull base and had complaint headache and various symptoms of cranial nerve involvement. Four of these five case showed improvement of neurologic symptoms after FFSRT. No significant neurologic complicaltion related to FFSRT was observed during follow-up periods. Tumor volumes were ranged from 3.9 to 50.7 cc and surface area ranged from 16.1 to $114.9cm^2$. IF ranged from 1.21 to 1.74. The average ratio of volume of prescription isodose shell to target volume was 1.02 that indicated the improvement of target coverage and dose distribution with FFSRT with conformal method compared to target coverage with FFSRT with multiple arc method. Conclusion: Our initial experience suggests that FFSRT with conformal method was relatively effective and safe modality in the treatment of recurrent head and neck cancer involving at or near skull base. Treatment benefit included good palliation of symptoms and reasonable radiographic response. However, more experience and additional follow-up are needed to better assess its ultimate role in treating these challenging patients.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.60-61
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• 2003

A new approach to reduce the computation time of genetic algorithm (GA) for making binary phase holograms is described. Synthesized holograms having diffraction efficiency of 75.8% and uniformity of 5.8% are proven in computer simulation and experimentally demonstrated. Recently, computer-generated holograms (CGHs) having high diffraction efficiency and flexibility of design have been widely developed in many applications such as optical information processing, optical computing, optical interconnection, etc. Among proposed optimization methods, GA has become popular due to its capability of reaching nearly global. However, there exits a drawback to consider when we use the genetic algorithm. It is the large amount of computation time to construct desired holograms. One of the major reasons that the GA' s operation may be time intensive results from the expense of computing the cost function that must Fourier transform the parameters encoded on the hologram into the fitness value. In trying to remedy this drawback, Artificial Neural Network (ANN) has been put forward, allowing CGHs to be created easily and quickly (1), but the quality of reconstructed images is not high enough to use in applications of high preciseness. For that, we are in attempt to find a new approach of combiningthe good properties and performance of both the GA and ANN to make CGHs of high diffraction efficiency in a short time. The optimization of CGH using the genetic algorithm is merely a process of iteration, including selection, crossover, and mutation operators [2]. It is worth noting that the evaluation of the cost function with the aim of selecting better holograms plays an important role in the implementation of the GA. However, this evaluation process wastes much time for Fourier transforming the encoded parameters on the hologram into the value to be solved. Depending on the speed of computer, this process can even last up to ten minutes. It will be more effective if instead of merely generating random holograms in the initial process, a set of approximately desired holograms is employed. By doing so, the initial population will contain less trial holograms equivalent to the reduction of the computation time of GA's. Accordingly, a hybrid algorithm that utilizes a trained neural network to initiate the GA's procedure is proposed. Consequently, the initial population contains less random holograms and is compensated by approximately desired holograms. Figure 1 is the flowchart of the hybrid algorithm in comparison with the classical GA. The procedure of synthesizing a hologram on computer is divided into two steps. First the simulation of holograms based on ANN method [1] to acquire approximately desired holograms is carried. With a teaching data set of 9 characters obtained from the classical GA, the number of layer is 3, the number of hidden node is 100, learning rate is 0.3, and momentum is 0.5, the artificial neural network trained enables us to attain the approximately desired holograms, which are fairly good agreement with what we suggested in the theory. The second step, effect of several parameters on the operation of the hybrid algorithm is investigated. In principle, the operation of the hybrid algorithm and GA are the same except the modification of the initial step. Hence, the verified results in Ref [2] of the parameters such as the probability of crossover and mutation, the tournament size, and the crossover block size are remained unchanged, beside of the reduced population size. The reconstructed image of 76.4% diffraction efficiency and 5.4% uniformity is achieved when the population size is 30, the iteration number is 2000, the probability of crossover is 0.75, and the probability of mutation is 0.001. A comparison between the hybrid algorithm and GA in term of diffraction efficiency and computation time is also evaluated as shown in Fig. 2. With a 66.7% reduction in computation time and a 2% increase in diffraction efficiency compared to the GA method, the hybrid algorithm demonstrates its efficient performance. In the optical experiment, the phase holograms were displayed on a programmable phase modulator (model XGA). Figures 3 are pictures of diffracted patterns of the letter "0" from the holograms generated using the hybrid algorithm. Diffraction efficiency of 75.8% and uniformity of 5.8% are measured. We see that the simulation and experiment results are fairly good agreement with each other. In this paper, Genetic Algorithm and Neural Network have been successfully combined in designing CGHs. This method gives a significant reduction in computation time compared to the GA method while still allowing holograms of high diffraction efficiency and uniformity to be achieved. This work was supported by No.mOl-2001-000-00324-0 (2002)) from the Korea Science & Engineering Foundation.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.2
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• pp.51-63
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• 2019

Purpose: Radiation therapy for breast cancer should consider the change in breast shape due to breathing and swelling. In this study, we evaluate the benefit of using virtual bolus for IMRT of left breast cancer. Materials and methods: 10 patients with early breast cancer who received radiation therapy after breastconserving surgery compared the VMAT and IMRT plans using the virtual bolus method and without using it. The first analysis compared the V95%, HI, CI of treatment volume, Dmean, V5, V20, V30 of ipsilateral lung, and Dmean of heart in VMAT plan made using the virtual bolus method(VMAT_VB) to the plan without using it(VMAT_NoVB) in case there is no change in the breast. In IMRT, the same method was used. The second analysis compared TCP and NTCP based on each treatment plan in case there is 1cm expansion of treatment volume. Result: If there is no change in breast, V95% in VB Plan(VMAT_VB, IMRT_VB) and NoVB Plan(VMAT_NoVB, IMRT_NoVB) is all over 99% on each treatment plan. V95% in VMAT_NoVB and VMAT_VB is 99.80±0.17% and 99.75±0.12%, V95% in IMRT_NoVB and IMRT_VB is 99.67±0.26% and 99.51±0.15%. Difference of HI, CI is within 3%. OAR dose in VB plan is a little high than NoVB plan, and did not exceed guidelines. If there is 1cm change in breast, VMAT_NoVB and IMRT_NoVB are less effective for treatment. But VMAT_VB and IMRT_VB continue similar treatment effect compared in case no variation of breast. Conclusion: This study confirms the benefit of using a virtual bolus during VMAT and IMRT to compensate potential breast shape modification.

• Journal of Sericultural and Entomological Science
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• v.2
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• pp.1-31
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• 1962

The purpose of this treatise is to prove the presence of cystine in silk fiber through wide sampling throughout all the sericultural processes of Bombyx mori.; also to show that disulfide cross linkages exist in the silk fiber. The conclusions reached were as follows: 1. Crystalline cystine was obtained from silk fibroin using Folin's Method. 2. Analytical data showing the cystine content of silk fiber and its related materials were obtained using Sullvan's Method as follows: Material Percent Cystine A. Mulberry leaf protein 0.175 B. Silkworm egg 0.33 C. Silkworm Body, matured, fat extracted, without silk gland 0.41 D. Silk gland, matured 1.23 E. Silkworm feces none F. Silkworm pupa, fat extracted 0.30 G. Silkworm moth, fat extracted 0.60 H. Raw Silk 0.22 I. Fibroin 0.175 J. Sericin 0.30 3. The presence of cystine in the silkworm was substantiated the existence of 0.175 % methionine in mulberry leaves and 0.12% methionine in the silk gland. 4. Part of the sulfhydryl compounds in the silk gland is believed to transfer to serine and methionine, with the former being secreted into the liquid silk finally as silk fiber and the latter used for nutritive purposes in the growing of silk gland tissue. 5. The cystine content is variable by mulberry species, silkworm species, sex, breeding process, and other culturing environments. 6. Hybrid silkworms require more nutritive amino acids for effective growth than the original parents, and secrete less of them as silk fiber. 7. From such an observation, the amino acid composition of silk fiber is believed to be fairly flexible. Cystine if included in the amorphous part of the fiber, especially in sericin. 8. The result from enriching the silkworm diet with pure cystine or wool cystine did not result in any advantage, therefore it is believed that the natural cystine and methionine contents in the mulberry leafaregoodenoughforsilkwormnutrition. 9. The disulfide cross linkage in silk fiber was verified by using the Harris Method. Contraction took place following the treatment of the fiber with various salts and acids. Comparisons were made with wool fiber. 10. During these experiments, the fibrious structure of silk fiber and the net-globular liquid form were photographed microscopically. It is believed that the globules of liquid silk are net-formed by the inter attraction of the OH ion of the globular peptide and the H ion of water as shown by the hair cracking behavior of the film. The net-globular protein precipitation from the mulberry protein solution showed that mulberry is a proper diet for the formation of fibrous protein in the silk fiber. 11. The significance of the presence of cystine in silk fiber as emphasized in this paper should result in modification of the general conception that cystine is absent from this fiber. NOTICE: A part of this treatise was presented at the annual Korea Sericultural Society meeting held in 1961.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.1
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• pp.1-25
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• 1996

The pathogenesis of atherosclerosis can not be summarized as a single process. Lipid infiltration hypothesis and endothelial injury hypothesis have been proposed and investigated. Recent developments show that there are many points of potential interactions between them and that they can actually be regarded as two phases of a single, unifying hypothesis. Among the many risk factors of atherosclerosis, plasma homocysteine and lipoprotein(a) draw a considerable interest because they are independent indicators of atherogenicity. Triglyceride (TG)-rich lipoproteins (chylomicron and VLDL) are not considered to be atherogenic but they are related to the metabolism of HDL cholesterol and indirectly related to coronary heart disease (CHD). LDL can of itself be atherogenic but the oxidative products of this lipoprotein are more detrimental. HDL cholesterol has been considered to be a favorable cholesterol. The so-called 'causalist view' claims that HDL traps excess cholesterol from cellular membranes and transfers it to TG-rich lipoproteins that are subsequently removed by hepatic receptors. In the so-called 'noncausalist view', HDL does not interfere directly with cholesterol deposition in the arterial wall but instead reflects he metabolism of TG-rich lipoproteins and their conversion to atherogenic remnants. Approximately 70-80% of the human population shows an effective feedback control mechanism in cholesterol homeostasis. Type of dietary fat has a significant effect on the lipoprotein cholesterol metabolism and atherosclerosis. Generally, saturated fatty acids elevate and PUFA lower serum cholesterol, whereas MUFA have no specific effect. EPA and DHA inhibit the synthesis of TG, VLDL and LDL, and may have favourable effects on some of the risk factors. Phospholipids, particularly lecithin, have an antiatherosclerotic effect. Essential phospholipids (EPL) may enhance the formation of polyunsaturated cholesteryl ester (CE) which is less sclerotic and more easily dispersed via enhanced hydrolysis of CE in the arterial wall. Also, neutral fecal steroid elimination may be enhanced and cholesterol absorption reduced following EPL treatment. Antioxidants protect lipoproteins from oxidation, and cells from the injury of toxic, oxidized LDL. The rationale for lowering of serum cholesterol is the strong association between elevation of plasma or serum cholesterol and CHD. Cholesterol-lowing, especially LDL cholesterol, to the target level could be achieved using diet and combination of drug therapy. Information on the link between cholesterol and CHD has decreased egg consumption by 16-25%. Some clinical studies have indicated that dietary cholesterol and egg have a significant hypercholesterolemic effect, while others have indicated no effect. These studies differed in the use of purified cholesterol or cholesterol in eggs, in the range of baseline and challenge cholesterol levels, in the quality and quantity of concomitant dietary fat, in the study population demographics and initial serum cholesterol levels, and clinical settings. Cholesterol content of eggs varies to a certain extent depending on the age, breed and diet of hens. However, egg yolk cholesterol level is very resistant to change because of the particular mechanism involved in yolk formation. Egg yolk contains a factor of factors responsible for accelerated cholesterol metabolism and excretion compared with crystalline cholesterol. One of these factors could be egg lecithin. Egg lecithin may not be as effective as soybean lecithin in lowering serum cholesterol level due probably to the differences of fatty acid composition. However, egg lecithin may have positive effects in hypercholesterolemia by increasing serum HDL level and excretion of fecal cholesterol. The association of serum cholesterol with egg consumption has been widely studied. When the basal or control diet contained little or no cholesterol, consumption of 1 or 2 eggs daily increased the concentration of plasma cholesterol, whereas that of the normolipemic persons on a normal diet was not significantly influenced by consuming 2 to 3 eggs daily. At higher levels of egg consumption, the concentration of HDL tends to increase as well as LDL. There exist hyper-and hypo-responders to dietary (egg) cholesterol. Identifying individuals in both categories would be useful from the point of view of nutrition guidelines. Dietary modification of fatty acid composition has been pursued as a viable method of modifying fat composition of eggs and adding value to eggs. In many cases beneficial effects of PUFA enriched eggs have been demonstrated. Generally, consumption of n-3 fatty acids enriched eggs lowered the concentration of plasma TG and total cholesterol compared to the consumption of regular eggs. Due to the highly oxidative nature of PUFA, stability of this fat is essential. The implication of hepatic lipid accumulation which was observed in hens fed on fish oils should be explored. Nutritional manipulations, such as supplementation with iodine, inhibitors of cholesterol biosynthesis, garlic products, amino acids and high fibre ingredients, have met a limited success in lowering egg cholesterol.